在类上有另一个类作为静态属性

问题描述

请阅读下面的示例*，但不要过分注意 EventEmitter 继承，它只是显示了类语法。

Read the example below*, but don't pay too much attention to the EventEmitter inheritance, please – it just shows the utility of the class syntax.

我意识到示例是不正确的ES2015，因为没有这样的事情作为 static class

I realize that the example is not correct ES2015, since there no such thing as a static class statement.

在ES2015中，这种工作方式最简单的方法是什么？

What would be the most syntactically lean way to make something like this work in ES2015?

class App extends EventEmitter {
  addPage(name) {
    this[name] = new App.Page;
    this.emit("page-added");
  }

  static class Page extends EventEmitter {
    constructor() {
      super();
      this._paragraphs = [];
    }

    addParagraph(text) {
      this._paragraphs.push(text);
      this.emit("paragraph-added");
    }
  }
}





---

我应该把它拆分并使用类表达式，如下所示？似乎不那么优雅。

---

Should I just split it up and use a class expression, like below? Seems less elegant.

class App extends EventEmitter {
  addPage(name) {
    this[name] = new App.Page;
    this.emit("page-added");
  }
}

App.Page = class extends EventEmitter {
  constructor() {
    super();
    this._paragraphs = [];
  }

  addParagraph(text) {
    this._paragraphs.push(text);
    this.emit("paragraph-added");
  }
};

推荐答案

是的，这是要走的路。如果您坚持使用声明，您必须之后进行 App.Page = Page 作业。

Yes, that's the way to go. If you insist on using a declaration, you'd have to make a App.Page = Page assignment afterwards.

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